These days, it seems, everyone is going green. In building and managing a real estate portfolio, conservation-minded individuals may be looking for ways to evaluate the environmental sustainability of a real estate portfolio. That is, it would be advantageous to provide builders, developers, property owners, etc. with a method and system of objectively evaluating the environmental sustainability of a portfolio in a manner that permits comparisons to be made between portfolios, properties, etc. In addition, it would be advantageous to provide a sustainability index that may aid in identifying trends over the life of the property or portfolio and which may be changed or adjusted as a direct result of management decisions in the real estate portfolio.